The present invention relates to communication in the industrial, scientific and medical (ISM) frequency bands, and more particularly, to a method for eliminating interference in a receiver, and to an associated apparatus.
The ISM frequency bands were originally reserved internationally for the use of radio frequency (RF) applications for industrial, scientific and medical purposes. Currently, the ISM frequency bands can also be used for license-free wireless communications. Regarding definitions of the ISM frequency bands, please refer to radio regulations of the International Telecommunication Union Radiocommunication Sector (ITU-R) for details.
As those skilled in the art may appreciate, the ISM coexistence problems (i.e. the problems of coexistence interference in the same ISM frequency band) are really a tough issue. More specifically, in a situation where the same frequency band is used by multiple wireless communication devices such as a Bluetooth (BT) device and a wireless local area network (Wireless LAN, WLAN) device complying with IEEE 802.11g specifications, as both the WLAN device and the BT device utilize the 2.4 GHz ISM band, mutual interference typically occurs while the WLAN device and the BT device transmit signals of the same band at the same time. According to the related art, the general solution is to perform collision avoidance with respect to the time domain or the frequency domain, and more particularly, to avoid any simultaneous system operation or to prevent using the same band/sub-band. However, some side effects may occur. For example, the collision avoidance may be involved with scheduling for WLAN packets such as wireless fidelity (Wi-Fi) packets, causing the throughput to be significantly decreased. In another example, the collision avoidance may be involved with adaptive hopping for BT packets, causing the spectral efficiency to be significantly reduced.
As discussed above, the throughput and/or the spectral efficiency are sacrificed for the collision avoidance. Thus, a novel method is required for reducing or eliminating interference without introducing any of the side effects.